Welcome to Vodafone Community
What's happening is that a techie at VF is working on implementing IPv6 and it's leaking onto the live network (sound familiar anyone). This has been happening since at least October/November.
If this is a computer, then you can go into the connection protocol settings and (for now) turn off IPv6. *Though at some point when VF migrate to IPv6 you'll need to turn it back on!
It's good to see that they are working on this, though bad that it's leaking and causing issues!